• Journal of Korean Society of Forest Science
• /
• v.95 no.2
• /
• pp.209-215
• /
• 2006

We investigated antioxidant capacity in leaves of 14 coniferous trees under field conditions. We focused on understanding the species characteristics on antioxidant systems and screening the coniferous tree species with the best antioxidant systems using their characteristics. The antioxidant capacity of 14 coniferous trees was divided into three groups. First group was Thuja orientalis and Chamaecyparis obtusa and those species had the highest content of ${\beta}$-carotene and xanthophyll. Second group, C. obtusa and Juniperus chinensis, used antioxidant enzymes to mitigate stress. C. obtusa represented high activity at superoxide dismutase (SOD), glutathione reductase (GR), and peroxidase (POD), and J. chinensis exhibited high activity at SOD, POD, catalase (CAT). Third group employed antioxidant such as ascorbic acid and ${\alpha}$-tocopherol. The antioxidant content of T. orientalis was the highest while that of Pinus parviflora and C. obtusa were the lowest. Few species belonged in three groups simultaneously, and most species belonged in at least one or two groups. In summary, we proposed that C. obtusa and T. orientalis had the highest antioxidant capacity while P. parviflora and P. desiflora for. multicalus had the lowest antioxidant capacity.

• Journal of Nutrition and Health
• /
• v.47 no.6
• /
• pp.484-488
• /
• 2014

Purpose: This study investigated the question of whether the addition of natural ingredients (pear fermented solution, celery powder, vitamin C) in curing agents may influence antioxidant activities and nutritional characteristics of smoked duck. Methods: Smoked duck samples with general or natural curing agent containing three additive ingredients were examined to determine total polyphenol contents, antioxidant activities, pH, TBARS, and food additives residue (nitrite ion, antioxidant, sodium glutamate). Results: Smoked duck with natural curing agent showed a higher level of total polyphenol content and antioxidant activities than smoked duck using general curing agent (p < 0.05). The pH and TBARS of smoked duck were significantly decreased by the addition of natural curing ingredients compared to those of smoked duck using general curing agent (p < 0.05). The residues of food additives were not detected in smoked duck using natural curing agent. Conclusion: Findings suggest that the addition of pear fermented solution, celery powder, and vitamin C in natural duck curing agent may improve the antioxidant activities and nutritional characteristics of smoked duck and provides health benefits.

• Journal of the Korean Society of Food Culture
• /
• v.30 no.6
• /
• pp.778-782
• /
• 2015

Demand for organic agriculture has greatly increased in the past decade. The objective of this study was to evaluate quality the characteristics and antioxidant activities of organically and conventionally grown carrots. Organically and conventionally grown carrots were harvested in Jeju Island, Korea. Carrot extracts were investigated for their antioxidative components (total phenolic and flavonoid contents) and their antioxidant activities (DPPH and ABTS radical scavenging activities). The quality characteristics of carrots were estimated in terms of hardness, length, weight, moisture contents, and soluble solid content (SSC). Conventionally grown carrots showed higher values than organic carrot in terms of hardness (p<0.05), but there was no significant difference in moisture contents or SSC. In the case of antioxidant activity, organic carrots showed a higher value for DPPH radical scavenging activity (p<0.05). However, there was no significant difference in other antioxidants. Consequently, quality characteristics and antioxidant activities were different between organically and conventionally grown carrots.

• Korean journal of food and cookery science
• /
• v.23 no.6
• /
• pp.899-907
• /
• 2007

The purpose of this research was to investigate the effects of herbs, including rosemary, thyme, oregano, ginger, and green tea, on the quality characteristics and antioxidant activity of Yagkwa. After 16 days of storage at $60^{\circ}C$, all the herb-added samples showed significantly lower values for acid, TEA and peroxide than the control. The samples with rosemary and thyme showed significantly higher antioxidant activities than the other samples. The samples with rosemary and ginger showed significantly lower L-values than the control sample and the samples with thyme, oregano and green tea showed significantly lower a-values than the control. For the b-value, the control sample had the highest value. In the sensory evaluation of the Yakgwa, there were no significant differences between the samples in terms of color, flavor and texture. For overall acceptability, the rosemary-added sample showed the highest score among the samples and the thyme-added sample showed a significantly lower score than the control. In the texture analysis, all the herb-added samples, except for green tea, showed higher hardness than the control. In conclusion, the addition of herbs would be a useful way to enhance the antioxidant quality of yakgwa and rosemary would be the best choice when considering antioxidant activity and sensory characteristics.

• The Korean Journal of Food And Nutrition
• /
• v.31 no.6
• /
• pp.821-827
• /
• 2018

Ecklonia cava which is a kind of phaeophyta and belongs to Laminariales Alariaceae is a perennial seaweed distributed over Jeju and Dokdo islands. The purpose of this study evaluate antioxidant activities of Ecklonia cava crackers. Crackers were prepared with different measurements (0, 2, 4, 6, 8 g) of Ecklonia cava; indicated as S1, S2, S3, S4 and S5, and are used to examine and compare antioxidant activities, and quality characteristics. Ecklonia cava powder was used, after being extracted with 70% ethanol in hot water and done in freeze dehydration. To examine antioxidant activities of Ecklonia cava and cracker, DPPH radical scavenging activity, total phenolic and reducing power were tested. Total phenolic content was 36.86 mg GAE/g. DPPH radical scavenging activity and reducing power showed good vitality as amounts of Ecklonia cava powder increased (p<0.001). pH level decreased as amounts of power increased. L (lightness) values and b (yellowness) values decreased with an increased concentration of Ecklonia cava powder (p<0.001), whereas (redness) values didn't show tendency. S5 indicated the lowest spreadness. According to sensory evaluation, S4 (6 g) was preferred the most in terms of color, flavor, taste, appearance, texture, and overall palatability. Results suggest that Ecklonia cava powder has antioxidant effect and is useful as a functional food resource.

• Korean Journal of Medicinal Crop Science
• /
• v.27 no.1
• /
• pp.9-16
• /
• 2019

Background: Various Schisandra chinensis (SC) varieties grow in diverse regions in Korea. However, there is no valid scientific evidence of these varieties. This study aimed to select the excellent resources in terms of the growth characteristics, antioxidant activities, and analysis of the active compounds of the SC collection. Method and Results: In total, 154 resources of SC were collected from various regions of Korea. The growth characteristics were measured by the number of fruit bunches, fruit number, and weight of 100 fruits. The antioxidant activities were investigated by analyzing the total flavonoid and total polyphenol contents and the radical scavenging activity of DPPH and ABTS. Schizandrin A, schizandrin c, gomisin a, and gomisin N were analyzed by HPLC. Each resource showed different growth characteristics. Among the antioxidative effects, the highest 20 resources showed high antioxidant activities in selected 29 resources. Analysis of the SC lignan index showed that all resources contained more than 1.16% of active compounds. Conclusions: All of the selected 29 SC resources were shown to have excellent growth characteristics, antioxidant activities, and bioactive compound richness. Especially, SC-004, SC-007, and SC-154 showed the best growth characteristics, and SC-22, SC-40, and SC-45 showed the best antioxidant activities and bioactive compound richness.

• Korean Journal of Food Science and Technology
• /
• v.54 no.2
• /
• pp.141-146
• /
• 2022

This study investigated the quality characteristics and antioxidant activities of preserved jams prepared by mixing various ratios of aronia and sugar. To analyze the quality characteristics, the total sugar, pH, moisture, maximum stress, hardness, total phenolics, 1,1-diphenyl-2-picrylhydrazyl (DPPH), trolox-equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and sensory characteristics of the preserved jams were measured. Lower aronia contents resulted in higher total sugar content, hardness, and strength, as well as lower moisture, total phenolic content, and DPPH, TEAC, FRAP, and ORAC values. In terms of the sensory characteristics, an aronia content of 30%, which was determined to have strong sweetness and texture, resulted in the lowest overall acceptability. In contrast, the highest preference was shown to an aronia content of 40%. In this study, quality characteristics and antioxidant activity experiments were conducted based on various ratios of aronia and sugar. The results are expected to be used as preliminary data for developing products that use domestic aronia.

• Korean journal of food and cookery science
• /
• v.25 no.2
• /
• pp.219-226
• /
• 2009

Red ginseng extract was added to Yanggaeng to determine a practical use for the herb which has medical usage and functionality. We examined the antioxidant activity and quality characteristics of Yanggaeng prepared with different amounts (as ratios of 1%, 2%, 3% to the total materials) of red ginseng extract, as well as those of commercial red ginseng Yanggaeng. The antioxidant activity of the Yanggaengs samples was estimated by the DPPH free radical scavenging activity, $ABTS^{+\cdot}$ scavenging activity, and reducing power. The antioxidant activity of the Yanggaeng increased as a result of the addition of the red ginseng extract. Levels of polyphenol compounds and flavonoids increased according to the extract concentration. The quality characteristics of the red ginseng Yanggaeng were estimated in terms of pH, sugar content, viscosity, color, texture profile analysis, and sensory evaluations. With increasing concentrations of the extract, viscosity and sugar content increased, but pH decreased. In terms of the overall palatability, color, taste, flavor, and hardness, the 3% red ginseng Yanggaeng was determined as the best among the tested samples. Also, the 3% red ginseng Yanggaeng had higher scores than the commercial red ginseng Yanggaeng.

• The Korean Journal of Food And Nutrition
• /
• v.35 no.1
• /
• pp.16-33
• /
• 2022

The quality characteristics and antioxidant activity of Tteokbokkidduk alone or supplemented with 3%, 6%, 9%, and 12% wheat bran powder were assessed, to increase use of the wheat bran by-product of wheat milling. The moisture content, pH, and starch elution of Tteokbokkidduk increased with increasing wheat bran powder, while the water absorption rate did not. The L color value decreased and the a and b values increased with increasing wheat bran powder. Scanning electron microscopy of Tteokbokkidduk prepared with 0% and 3% wheat bran powder revealed uniform pore size distribution. In terms of texture profile analysis, hardness and chewiness increased, while cohesiveness decreased with increased content of wheat bran powder. Acceptance was highest for samples with 6% wheat bran powder. Quantitative description analysis (QDA) revealed increased brownness, roughness, nutty, bitterness, astringency, savory character, and hardness, and decreased adhesiveness, springiness, and chewiness with increased wheat bran powder. Principal component analysis (PCA) revealed highest overall acceptance of samples prepared with 6% wheat bran powder, reflecting the relatively low values of detrimental sensory characteristics. Antioxidant activities of Tteokbokkidduk increased as wheat bran powder content increased. The addition of 6% wheat bran powder resulted in excellent Tteokbokki in terms of acceptance, quality, and antioxidant activity.

• The Korean Journal of Food And Nutrition
• /
• v.35 no.6
• /
• pp.499-512
• /
• 2022

This study investigated the quality characteristics and antioxidant effects of rice cookies containing different percentage of freeze-dried plum powder (3%, 5%, 6%, and 12%). The density of the dough and the thickness of the rice cookies from the control group and the additive group were not significantly different. The pH value of the dough, its moisture content and spread factor, as well as the Hunter's L and b values of the rice cookies significantly decreased as the amount of dried plum powder added increased. However, the sweetness, hardness, thickness, Hunter's a value, total polyphenol, total flavonoid and anthocyanin contents, DPPH and ABTS free radials scavenging activity, and ferric reducing antioxidant power of the rice cookies significantly increased as the amount of dried plum powder added increased. Overall, the results of this study showed that adding dried plum power enhanced the antioxidant activities and quality characteristics of rice cookies.